In emerging Machine-to-Machine (M2M) applications e.g. intelligent systems like the smart grid and the smart city, it is anticipated that a large number of small and smart devices such as wireless sensor nodes will be deployed. These nodes are expected to facilitate continuous sensing and gathering of data for observing/monitoring the object of interest. Then, the collected information needs to be somehow passed to a control centre in order to enable adaptation decision and realize system automation. It follows that there is an increased demand for transport of data on multi-hop routes, i.e. on routes between a source node and a destination node, involving one or more intermediary nodes.
Transporting raw data over multi-hop wireless links can be costly both in terms of time as well as resources. The total amount of traffic to be forwarded on multi-hop routes can be significantly reduced using in-network processing and data aggregation, particularly by pre-processing of correlated information. For example, energy-efficient data aggregation and fusion schemes can pre-process the data within the network and only send the processed result with much less data volume compared to its original size. Thus, these schemes can reduce redundant traffic and avoid data overloading for future wireless networks. However, a suitable data forwarding scheme is needed as a prior condition in order to efficiently compute and relay data.